M.O. Dolivo-Dobrovolsky - Russian innovator-electrician and his inventions

A talented Russian is considered one of the founders of the technique of applying alternating currents. engineer and inventor Mikhail Osipovich Dolivo-Dobrovolsky. His name is associated with work in the field of creating the technique of three-phase alternating currents. He is the creator of a simple and reliable asynchronous motor to use. An engine of this design is used today. All elements of the three-phase system were created by Dolivo-Dobrovolsky.

Mikhail Osipovich was born on January 2, 1862 in the family of an official. He became the firstborn in a large family Dolivo-Dobrovolsky, who at that time lived in the city of Gatchina. In 1873, the Dolivo-Dobrovolsky family moved to Odessa, where the childhood and youth of the future talented inventor passed. There, in Odessa, he brilliantly graduated from the Odessa Real School.

Then he entered the Riga Polytechnic Institute. But Mikhail Osipovich did not have time to finish it. For participating in a student solidarity strike with workers at Riga factories, he was expelled from the institute without the right to enter any Russian educational institution. It is this fact that played a crucial role in the life of the inventor and the history of world electrical engineering.

With the help of his uncle, the young Dolivo-Dobrovolsky managed to go abroad and there he entered the Higher Technical School in the German city of Darmstadt. In the period from autumn 1881 to 1884, M.O. Dolivo-Dobrovolsky studied at the Faculty of Mechanical Engineering, while studying electrical engineering. Having graduated with honors from the Higher Technical School, Mikhail Osipovich remained an assistant in him in the recently opened Electrotechnical Laboratory.

In the years 1884-1885. the first publications of Dolivo-Dobrovolsky on the issues of electrical engineering appear in the press. His work did not go unnoticed. In 1887, Mikhail Osipovich was invited to work by Emil Rotenau, who was then head of the company Universal Electricity Company. After a few years, Mikhail Osipovich himself became the director of the company, which he would head until the end of his life.

The first works of M.O. Dolivo-Dobrovolsky were associated with DC systems. Studying the problems of applying direct current, he also followed the most important events of theoretical thought. He familiarized himself with the work of the Italian physicist Galileo Ferraris on a rotating magnetic field.

In his works, Ferraris argued that the efficiency of an asynchronous two-phase motor would not exceed 50% and therefore, multiphase AC electric machines would not be widely used. Beginning in 1888, M.O. Dolivo-Dobrovolsky began to study multiphase systemsfor which he established a special name, then established in the terminology of electrical engineering. Having deeply studied DC machines, he made the correct conclusion about the fallacy of the Ferraris theory.

For his work, Dolivo-Dobrovolsky began to use not two-phase current, as Ferraris and Nikola Tesla did, but three-phase, that is, three alternating currents, each of which is phase shifted by 120 degrees.

In 1888, after a series of trials, he built first three-phase alternator with a capacity of about 3 kilowatts and with the help of it he activated his first three-phase motor with a Gram ring statorfed at three points and a rotor in the form of a solid copper cylinder.

Continuing the traditions of their talented compatriots (P. N. Yablochkov, B.S. Jacobi) Dolivo-Dobrovolsky worked on the possibility of applying in practice alternating current. And so, starting since 1891, a new page in the history of electrical engineering begins. This year, an electrical test in Frankfurt successfully tested three-phase current systems in the form of electricity transmission over a distance of 175 kilometers from Lauffen Falls to Frankfurt.

Three-phase generator in Lauffen am Neckar (Baden-Württemberg) - 1881.

The Lauffen power transmission was the first AC transmission in the world and served as the beginning of the dominance of AC, which continues to this day. The three-phase system created by Dolivo-Dobrovolsky was widely used in a short time. But the merit of a talented Russian engineer is not only in the invention of a method for transmitting alternating current over long distances, but also in creating devices that are necessary for the operation of three-phase alternating current. A large number of devices created by him are used by electricians in an unchanged form.

M.O.Dolivo-Dobrovolsky put a lot of work to propagate the introduction of three-phase alternating current in science and technology. With the help of disputes, reports, monographs, he was able to achieve that he had practically no ideological opponents left.

In December 1899, at the First All-Russian Electrotechnical Congress, Dolivo-Dobrovolsky spoke with report "Modern development of three-phase current technology". In it, he summed up his activities: the development of the theory of transformers, the design of new measuring instruments, engines and other devices.

Three-phase asynchronous motor of Dolivo-Dobrovolsky

Despite the fact that M.O.Dolivo-Dobrovolsky lived and worked abroad, he retained Russian citizenship. With the outbreak of World War I in 1914, he moved to Switzerland, where he remained until 1918. Then he returned to Germany to continue work. But chronic heart disease disrupted his plans.

The last years of his life, Mikhail Osipovich devoted to the study of the method of transmitting electricity over long distances using high-voltage direct current. He saw the future development of electrical engineering in long-distance high-voltage direct current power transmission via underground cables. Dolivo-Dobrovolsky worked on this issue until the last days of his life. November 15, 1919 he died of heart disease. His death was met with sorrow by engineers around the world.

Bust M.O. Dolivo-Dobrovolsky

The most talented engineer and inventor M.O. Dolivo-Dobrovolsky was multilaterally educated and cultural. His contribution to the development of electrical engineering and, in particular, in the field of application of three-phase alternating current systems is enormous. Continuing the work of his compatriots, Mikhail Osipovich managed to advance science and technology far ahead. The work of Russian inventors forever entered the history of world electrical engineering.